错误 1248 (42000)：每个派生的 table 必须有自己的别名，存在别名（内部查询组和具有）

Question

我需要 select 非官方 lang-s 是官方语言两倍的国家，+ 官方是 2+

MYSQL 查询：

SELECT c2.countrycode , sum(c2.isOfficial) as isFalse
FROM countrylanguage as c2
 INNER JOIN (
        select c.countrycode , sum(c.isOfficial)as isOffTrue 
        from countrylanguage as c 
        where c.isOfficial='T' 
        group by c.countrycode 
        having sum(c.isOfficial)>1)
         ) as cisT 
 ON cisT.countrycode = c2.countrycode 
  where c2.isOfficial='F' 
  group by c2.countrycode 
  having sum(c2.isOfficial)>cisT.isOffTrue*2

但我收到别名错误，无法确定问题的根本原因，你能帮我吗？

稍后....

RC: 额外 ) 加入

NExt 错误：无法识别内部 sum() 别名，请您帮忙？

  SELECT c2.countrycode , sum(c2.isOfficial) as isFalse
FROM countrylanguage as c2
 INNER JOIN (
        select c.countrycode , sum(c.isOfficial) isOffTrue 
        from countrylanguage as c 
        where c.isOfficial='T' 
        group by c.countrycode 
        having sum(c.isOfficial)>1
         ) as cisT 
 ON cisT.countrycode = c2.countrycode 
  where c2.isOfficial='F' 
  group by c2.countrycode 
  having sum(c2.isOfficial)>(cisT.isOffTrue*2);

错误 1054 (42S22)：'having clause'

中的未知列 'cisT.isOffTrue'

加法：

Table:

 +-------------+---------------+------+-----+--------+
| Field       | Type          | Null | Key | Default |
+-------------+---------------+------+-----+---------+
| CountryCode | char(3)       | NO   | PRI |         |
| Language    | char(30)      | NO   | PRI |         |
| IsOfficial  | enum('T','F') | NO   |     | F       |
+-------------+---------------+------+-----+---------+

我像下一个一样更改了查询并且成功了，购买我仍然没有得到之前失败的 RC

SELECT c2.countrycode, sum(c2.isOfficial) as isOffFalse, c1.isOffTrue 
  FROM (
select c0.countrycode, sum(c0.isOfficial)as isOffTrue 
from countrylanguage c0 
where c0.isOfficial='T' 
group by c0.countrycode having sum(isOfficial)>1
) as c1, countrylanguage as c2
  where c1.countrycode = c2.countrycode 
and c2.isOfficial='F' 
group by c2.countrycode 
having sum(c2.isOfficial)>(c1.isOffTrue*2);

Answer 1

您正在加入

ON cisT.countrycode = c2.countrycode

但 cisT 中不存在国家代码列 table。

错误 1248 (42000)：每个派生的 table 必须有自己的别名，存在别名（内部查询组和具有）

ERROR 1248 (42000): Every derived table must have its own alias , alias are present (inner query with group and having)

mysql

sql

mysql-error-1054